Gas heater



FIG. 1 is a front and right side perspective view of a gas heater showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a top plan view thereof; and

FIG. 6 is a bottom plan view.

The broken line showing of an electrical cord in FIGS. 1, 2, 4, 5 and 6 and a handle in FIGS. 1, 4 and 5, is for illustrative purposes only, and forms no part of the claimed design. 

The ornamental design for a gas heater, as shown and described. 